A constant current ionization excitation circuit and control method

Abstract

The invention discloses a constant-current ionization excitation circuit and a control method. The circuit comprises a first triode, an excitation coil and a constant current source, wherein the constant current source comprises a second triode and a first resistor; the first triode is a high-power radio frequency NPN transistor for onset; the second triode is a PNP triode for current stabilization; the first resistor is connected between the emitter of the PNP triode and a DC voltage source and is also connected between the collector of the NPN triode and the DC voltage source. The control method comprises steps: if the ionization source does not emit light, a high-level signal is inputted to a switching circuit to enable the excitation coil to work at a high power value, and the ionization source is excited to emit light; and if the ionization source emits light, a low-level signal is inputted to the switching circuit to enable the excitation coil to work at a low power value, and the ionization source is kept in a light emitting state. Thus, the oscillatory stability in a high power state can be improved, and the ionization stability is improved.

Description

technical field [0001] The application relates to the field of radio frequency circuits and testing, in particular to a constant current ionization excitation circuit and control method for atomic clocks. Background technique [0002] The ionization source (or spectral lamp) is a key component of many atomic clocks. These spectral lamps or ionization sources are usually a glass bubble filled with alkali metal, buffer gas or injected hydrogen, and then excited by a high-power radio frequency signal. The power ranges from a few W to tens of W, ionizes the buffer gas in the glass bubble to emit the required spectral lines, or further excites the inner alkali metal to emit the required spectral lines. For example, rubidium clocks and mercury ion clocks need a spectral lamp to emit the spectrum required for atomic transitions, while hydrogen clocks need to ionize hydrogen gas in a glass bubble to form an ionization source, and then leak it into a microwave resonant cavity. The i...

AI Technical Summary

Problems solved by technology

The ionization stability of the ionization source (or spectral lamp) seriously affects the performance of the atomic clock, leading to failure in severe cases

The ionization excitation circuit is generally a triode oscillator, and its oscillation power is easily affected by factors such as ambient temperature and power supply voltage, which in turn affects ionization stability.

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